It’s been a couple years since I tried it, but here are the steps I did back then to capture screenshots:
I can’t remember how good the quality was, but I think it was the same quality as Capture Age showed… which was good quality isn’t it? It seemed decent at the time. But is it bad? What do find as bad about your captures, quality-wise? If my process above is different than what you tried, you might try my steps and see if it’s any better